DATASHEET
ISL78692
Li-ion/Li-Polymer Battery Charger
FN8692
Rev.1.00
Mar 29, 2017
The ISL78692 is an integrated single-cell Li-ion or Li-polymer
battery charger capable of operating with an input voltage
as low as 2.65V (cold crank case). This charger is designed to
work with various types of AC adapters or a USB port.
Features
• Complete charger for single-cell Lithium chemistry batteries
• Integrated power transistor and current sensor
• Reverse battery leakage 700nA
The ISL78692 operates as a linear charger when the AC
adapter is a voltage source. The battery is charged in a CC/CV
(constant current/constant voltage) profile. The charge current
is programmable with an external resistor up to 1A. The
ISL78692 can also work with a current-limited adapter to
minimize the thermal dissipation.
• 1% initial voltage accuracy
• Programmable CC current up to 1A
• Charge current thermal foldback
• NTC thermistor interface for battery temperature alert
• Accepts CV and CC types of adapters or USB bus power
• Preconditioning trickle charge
The ISL78692 features charge current thermal foldback to
guarantee safe operation when the printed circuit board’s
thermal dissipation is limited due to space constraints.
Additional features include preconditioning of an
over-discharged battery, an NTC thermistor interface for
charging the battery in a safe temperature range and
automatic recharge. The device is specified for operation in
ambient temperatures from -40°C to +85°C and is offered in
a 3x3mm thermally enhanced DFN package.
• Guaranteed to operate down to 2.65V after start-up
• Ambient temperature range: -40°C to +85°C
• AEC-Q100 qualified
Applications
• Automotive systems
• eCall systems
Related Literature
• Technical Brief TB363 “Guidelines for Handling and
Processing Moisture Sensitive Surface Mount Devices
(SMDs)”
• Backup battery systems
• Technical Brief TB379 “Thermal Characterization of
Packaged Semiconductor Devices”
• UG001, “ISL78692EVAL1Z Evaluation Board User Guide”
CONSTANT
CURRENT
MODE
CONSTANT
VOLTAGE
MODE
TRICKLE
MODE
INHIBIT
VIN
BATTERY
PACK
ISL78692
INPUT VOLTAGE
VCH
5V
VIN
V
BAT
BATTERY VOLTAGE
R
1
C
C1
10µF
2
R
100k
1
100k
+
-
TEMP
2x10µF
FAULT
STATUS
EN
R
1k
1
VTRICKLE
V2P8
IREF
R
160k
1
EN
ICHARGE
C3
TIME
GND
1µF
CTIME
15nF
CHARGE CURRENT
I
CHARGE/10
TIMEOUT
FIGURE 1. TYPICAL APPLICATION
FIGURE 2. TYPICAL CHARGE CURVES USING A CONSTANT
VOLTAGE ADAPTER
FN8692 Rev.1.00
Mar 29, 2017
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